30 Years of Air Quality Trends in Japan

Atmosphere

Shinji Wakamatsu¹  Akiyoshi Ito²  Tazuko Morikawa²  Shinji Kobayashi³ 

[1] Institute of Integrated Atmospheric Environment (IIAE), Emeritus of Ehime University, Matsuyama 790-8566, Japan;Japan Automobile Research Institute, 2530 Karima, Tsukuba 305-0822, Japan;National Institute for Environmental Studies (NIES), 16 Onogawa, Tsukuba 305-8506, Japan;

关键词: air quality trend;    particulate matter;    ozone;    emission control;    inventory;    air quality standard;   

DOI  :  10.3390/atmos12081072

来源: DOAJ

【 摘 要 】

The aim of this paper is to obtain information that will contribute to measures and research needed to further improve the air quality in Japan. The trends and characteristics of air pollutant concentrations, especially PM_2.5, ozone, and related substances, over the past 30 years, are analyzed, and the relationships between concentrations and emissions are discussed quantitatively. We found that PM_2.5 mass concentrations have decreased, with the largest reduction in elemental carbon (EC) as the PM_2.5 component. The concentrations of organic carbon (OC) have not changed significantly compared to other components, suggesting that especially VOC emissions as precursors need to be reduced. In addition, the analysis of the differences in PM_2.5 concentrations between the ambient and the roadside showed that further research on non-exhaust particles is needed. For NOx and SO₂, there is a linear relationship between domestic anthropogenic emissions and atmospheric concentrations, indicating that emission control measures are directly effective in the reduction in concentrations. Also, recent air pollution episodes and the effect of reduced economic activity, as a consequence of COVID-19, on air pollution concentrations are summarized.

【 授权许可】

Unknown